Razor-Thin Lead for the GOP

Razor-Thin Lead for the GOP
Democrats have slightly increased their chances of holding on to the Senate, so Republicans need to ensure red states stay red.
By Charlie Cook

Are things getting better for Senate Democrats? Certainly many of the better (more reliable) statistical models seem to suggest they are. Nate Silver’s FiveThirtyEight moved from a 64 percent chance of the GOP gaining a majority, predicted on Sept. 3, to a 54.7 percent chance on Sept. 15. As of Sept. 16, The New York Times’ Upshot model, nicknamed Leo, put GOP chances at 51 percent; they were at 67 percent on Aug. 26. The conventional wisdom also appears to have shifted over the past week. What, if anything, has happened to cause this shift?

Polls show Democratic Sen. Kay Hagan of North Carolina leading GOP challenger Thom Tillis. (Chip Somodevilla/Getty Images)A little bit of the change can be attributed to methodological shifts among forecasters; as statistical modelers add new elements to their computations, the new data affect the output of their models. But that does not explain all of the shift. The most significant reason seems to be that in this year’s competitive Senate races in purple states—those where either Barack Obama or Mitt Romney won by narrow margins—Democrats are, for the most part, holding their own or even improving their odds.

In North Carolina, for example, Democratic incumbent Kay Hagan has now built a lead over GOP state House Speaker Thom Tillis in both private and public polling. Hagan led by 4 points in the Sept. 5-9 Elon University poll, 45 percent to 41 percent among likely voters. It is still a competitive race, and Tillis could very well win the seat, but for now the momentum seems to be with Hagan.

In the fight for the open seat in Michigan, Rep. Gary Peters seems to be getting a firmer grip on the contest, and his chances of winning have increased. Colorado’s Democratic incumbent, Mark Udall, has built up a small but measurable lead over GOP Rep. Cory Gardner. Again, this is still a very close race, but Udall looks a bit better now than he did earlier in the cycle. In Iowa, Rep. Bruce Braley seems to have a tiny lead over GOP state Sen. Joni Ernst. The Democrat is still under-performing compared with how he should be doing, but he now looks a little better.

Models also show Republican Pat Roberts in Kansas shifting from safe to endangered, although it is far from certain which party independent Greg Orman would sit with if he upset Roberts (or, for that matter, how reliable a vote he would be for Democrats if he were to win and join their conference). Rather than an obvious shift in Democrats’ favor, I still see uncertainty in Kansas.

At the same time, in Georgia—not quite a swing state but not deeply red, either—things are looking up for Republicans, with David Perdue starting to pull away from Democrat Michelle Nunn, although the race is still very competitive. Polls are producing conflicting results in New Hampshire; some show former Sen. Scott Brown closing the gap with incumbent Democrat Jeanne Shaheen, but I remain skeptical that the race has moved that much. Brown is a transplant who hasn’t worked out as well as Republicans had hoped.